Insulator



Fab. 20, 1923. 1446135.

L. STEINBERGER.

IIIIIIII R.

Patented Feb. Z0, 1923.

UNITED STATES 1446,135 PATENT OFFICE.

LOUIS STEINBERGER OF BROOKLYN, NEW YORK.

IN'SUIATORL A pplication filed March 15, 1917. Serial NZo-. 154,914.

T all whom. z't mag concem:

Be it known that I, LOUIS STEINBERGER,& citizen 0f the United States, and a resident of the borough of Brooklyn, county of Kings, city and State of New York, have invented certain new and useful Improvements in Insulators, of which the following -is a specification.

This inventionrelateSv t0 improvements in insulating devices, commonly known as pin insulators anal the particular type -to 'Which the invention relates is that which may .be secured rigiclly at on'e end to a suitable support and is capable not only of withstandirig mechanical strains, but high potentials.

()ne 0f the objects of my -invention is to provide a pin insulator wh ich is simple and efficient in construction, the parts of which a1'e easily assembled.

Another obfiect is t0-provide neans f01' securely holding the insulating material to its supporting base in such a position asto minimize the danger of deterioration due to the effects of dielectric stress on the insulator.

Another object is t0- locate the locking m eans betweeh the supporting pin and the .insulating material at a maximum distance from the line.

Another object is to provide a metal lined cavity in an insulator within which the sup- F ig. 1 is a vertical section through my improved compound insulzttor and support. 'Fig. 2 isa front elevation 0f the centre pin to which the insulato1 is secured.

Fig. 3 is d front elevation of a modified form 0f pin shown 'broken away at the lower portion thereof.

F ig. 4 is a section in line 441 of Fig. 2.

In the drawings like reference characters refer to like parts. w

A is a cross arm or support t o which the supporting pin is attached, B is the supporting pin and C is the lower anal D the upper secti on 0f the insulator. The lower portion 10 of the supporting pinextends through and closely fits the opening 11 in thecross arm A, the extreme lower end0f the pin being preferably screw-threaded at 13 to engage With lock nuts 14. Extending radially from the pin and longitudinally there- 0f are a plufality oitfin shaped projections 15 so shaped that their under-sides at 16 Will rest secu'rely u'pon a plate 16' on the cross arm A. Screw-thread's 17 are provided on the-{31m immediately above the upper ends of the projecting fins 15 and these threads extend along the pin for a suitabledistance t0 accomplish the purpose, for 'which they are designed which Will be hereinafter described. The p-in which is substantially4 con ical in shape extends upwardly a suitable distance, the top of Which is provided eithe1 with a convex surface as shown in F ig. 2, 01' a flat surface as showh in Fig. 3. A suitablyformed metal lining 20 is provided for the cai ity in the insulator C so as to fit the same closely throughout the length of the cavity to the base 0f the screw-threaded portion, the'lower en d 0f the met'al lining at 21 having screw-threads 30 formed therein t0 engage the screw-threads 17 on the pin.

latingmaterial, bu't I prefer to use in this construction a material known in the art as Electrose. Projeeting radially from the body of the lower portion of the insulator are a series of circurnferential sheds or hoods 25, the diameter of the respetive hoods progressively decreasing from top t0 bottom. This portion 0f the insulator has' formed therein a central longitudinal bore or cavity 26'0pen at its lower end at 27 and closed at its inner end at 28 and so shaped that the pin and the metal lining will completely fi1l the same. Extending inwardly from the lower end f the cavity for a short distance only are a series of screw-threads 29 which closely fit ancl engage the screwthreads 30 0f the metal lining and by means of Which the pin anal insulator are removably held togeth'er.

As indicated in the drawings, it is my purppse to provide screwthreads at the base 0f the bore of the insulator to extend only a sfiicient distance to securely hold the insulator in place and at a point Which is remote from the point of contact of the line -wire With the insulator. The remaining portion of the Walls of the boreis smooth and the bore und pin are so shaped that a close und snug fitting will be made between them.

My purpose in providing a screwthread of minimum extent or surface is to lessen the number of ridges 0r protrusions which when present tend t0 cause the insultor t0 puncture a.t those points owing to the concentration of electro-static stresses due t0 the position o f the surface of the screwthreads. The smooth surfaces of the bore and pin which extend throughout'the greater portion of the same greatly reduces this danger.

The upper ei1d of the lower section of insulating material is convex at 31 and is provided with screw-threads 32 at the base of the convex portions to Which is fitted the other section 0f the insulator which is provided with a cavity 33 complementary in shape t0 the convex and screw-threaded end of the lower section. 'Ihwupper section D is held in placeto the lovver section O by means of the screw-threads above described. The upper section 0f insulator is provided With a shed 01" hopd 34 extending radially and circumferentially therefrom and having a diameter slightly greater than the diameter of the shed 01 hood 25 next below. The under side of the shed or hood 34 is provided With a vggwed under surface in order t0- more efl'ectually lengthen the insulating path. A groove 35 is arranged at th.e top 0f section D of insulating material exte-nding diametrically along the same f0r the reception of the line wire, and a circumferential groove 36 is also provided just above its shed 01' hood 34 for t=he reception of a securing wire.

While I have preeferably employed a metallic lining for the cavity for the supporting pin throughout the surface thereof which engages the insulating material, this metal lining may be dispensed with and the pin fitted directly -t0 the b0re 01 cavity in the insulator by means of the screw-threads as above described. The pin is pref'erably made of Wo0d 'or may obviously 106 constructed 0f any other 'suitable material and ma'y even be formed entirely of metal.

It is to be understood that the above descrip1tion and drawings are merely illustra tive and the invention is not to be limited the pin fitting und extending into said bore,

said bore and pin having their adjacent surfaces smooth and free from protubemnces 01 projections throughout the upper and greater .portion of their extent, mutually engagi ng securing means between the insulator and the supprting pin, said securing means located on1y ab the lower end or side 0f the insulator and remote from the apex of the pin, and a seat f0r the 1ine wire 0n the upper end 01 side 0f the insulator remote from said secur'ing means.

2. In an insulator, a body of insulati rig material provided with a line wire seat at one end and a conically shaped b0re through the central portion thereof closed at one end and open at the other, a metal liriing forsaid b0re secure'd thereto on1y at the base of the insulating' body, and a supportin g pin secured by screw threads to said miatal lined' bore at the same point on-ly.

3. A pin insulator provided with a pin Sek curing bore, a metal lining for said bore and means for removably securmg the h'ningto y the bore at its base only.

4. An insulator body provided with means for securing the 1ine Wi1'e at one end and having a conical bore in the central portion thereof, the wa1l of the borebeing smooth throughout the grez'zter portion of its length an{il provided with screw threads at its base 011 y.

In witness whereof I have hereunto set my h&nd ab borough of'Manhattan, county of New York. and State 0f New York, this 12th day of March, 1917.

LOUIS STEINBERGER.

In presence of- ZITA M. GRAHAM, IS:ABEL R. RICI-IARDS. 

